hold in the play button and the middle button for 10 secs until the apple comes on the screen, it worked for me :) xx
Occasionally an iPod or iPhone may freeze or fail to respond to your commands. This can happen for a number of reasons and does not necessarily indicate a serious problem: http://www.methodshop.com/gadgets/ipodsupport/restart/index.shtml
Take care !!What shall I name my iPod?